2013-01-31_REPORT - M1973021 (2)

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Small blocks may form in this area due to the orientation of the highwall and jointsets of the rock. These blocks are anticipated to be limited in size, and should be retained on the bench below the highwall. Due to the moderately to highly fractured nature of the rock, raveling is to be expected in this area. Raveling from this zone should be retained on the bench below the highwall and is anticipated to cause only local operational delays. • Stations 3 +10 through 4 +30 were unmappable due to nearly complete debris and rubble coverage. The condition of the highwall is unknown in this section. • Stations 4 +30 through 6 +70 contain no highwall (Bench 6640 daylights to the east) and is only utilized at a placeholder for continuity of the scanline. • Stations 6 +70 through 7 +70 were unmappable due to nearly complete debris and rubble coverage. The condition of the highwall is unknown in this section. • Stations 7 +70 through 9 +95 consisted of highly fractured granitic gneiss. The foliation strike varies in this area due to minor folding and ranges from 225 to 270 degrees. Foliation dips ranged between 20 and 45 degrees southeast. Foliation spacing ranges approximately from 2 inches to more than 2 feet, and foliation apertures were open to very wide and slightly rough to rough. The primary joint set strike ranges from 290 to 340 degrees and generally dips from 50 to 70 degrees southwest. A second primary joint set is apparent in the highwall but is not mappable due to the highly fractured nature of the rock in this section. The spacing of the primary joint set varied widely, but averaged approximately 18 inches. Joint apertures were open to very wide with slightly rough to rough faces. The highwall between approximate stations 9 +50 and 9 +95 was unmappable due to partial debris and rubble coverage. The condition of the highwall is unknown in this section. • Stations 9 +95 through 14 +95 consisted of moderately to highly fractured granitic gneiss. The foliation strike varies in this area due to minor folding and ranges from 315 to 340 degrees. Foliation dips ranged between 25 and 50 degrees southwest. Foliation spacing ranges approximately from 2 inches to more than 2 feet, and foliation apertures were moderately open to very wide and slightly rough to rough. The primary joint set strike ranges from 90 to 350 degrees and generally dips from 65 to 80 degrees northeast. A second primary joint set is evident in this area and exhibits a strike of 100 to 265 degrees with a dip of 40 to 75 degrees southeast. The spacing of the primary joint sets varied widely, but averaged approximately 18 inches. Joint apertures were moderately open to very wide with slightly rough to rough faces. • A secondary joint set is evident in this area and exhibits an average strike of 125 to170 degrees with an average dip of 43 degrees northeast. The spacing of the secondary joint set varied, but averaged greater than 6 feet. Joint apertures were moderately open with slightly rough to rough faces. Small blocks may form in this area due to the orientation of the highwall and jointsets of the rock. These blocks are anticipated to be limited in size, and should be retained on the bench 9 Morrison Quarry Annual Report 2012 P \23514 \133- 23514- 13002\Dehverables\Deliv -01 -2012 Annual Report \ Annual Report _ 2012 _ Geotech doc January 2013